Abstract: A magnetic disk cartridge retains a rotational magnetic disk in a case through liners, which contact the associated surfaces of the disk and each have multiple long protrusions formed almost uniformly and almost in parallel to one another on the whole surface on the disk side. As the magnetic disk rotates, the angle of the disk surface contacting the long protrusions can gradually change, thus ensuring removal of dust from the disk. In additon, this structure can reduce the frictional resistance between the liner's surface and magnetic disk, which contributes to faster rotation of the disk.

Abstract: A tunnel lining process and an apparatus for use in the process in the prior art are improved in order to greatly enhance a lining speed and to facilitate the work of placing concreate for lining. The improvements reside in that a pressing form for pressing a tunnel concrete lining and a side form to be positioned on the side of the pressing form opposite to an already placed concrete lining are constructed as separate bodies in distinction from the prior art. After the pressing form and the side form have been disposed along an excavated surface of a tunnel, lining concrete is placed in a space delimited by the both forms, the excavated surface and the already placed concrete lining so as to press the lining concrete onto the excavated surface to be lined.

Abstract: A method and test composition for colorimetrically determining hydrogen peroxide in a sample includes a chromogen of the formula: ##STR1## which is reacted with hydrogen peroxide in the sample in the presence of peroxidase. The absorbancy of the reaction solution is then measured.

Abstract: The present invention provides a method for the determination of bilirubin which comprises reacting the bilirubin with a compound represented by the formula ##STR1## and determing the pigment thus formed.